Patent GB-365647-A (GB)
Title: Improvements in or relating to automatic switches for use in telephone or like systems
IPC: H01H67/16
Filed: 1930-10-24
Abstract: 365,647. Automatic exchange switches. AUTOMATIC TELEPHONE MANUFACTURING CO., Ltd., Strowger Works, WOODLAND, C. R., 45, Warnerville Road, Broadgreen, both in Liverpool, and EDDOWES, S. G., 8, Seaview Avenue, Eastham, Cheshire. Oct. 24, 1930, No. 32016. [Class 40 (iv).] In a switch of the Strowger type, the mechanically operated spring sets are mounted substantially in vertical alignment with the spring sets of the controlling relays, and the tags of all spring set s project through apertures in the mounting plate of the switch so that all connections are made from the rear. The spring sets are arranged symmetrically in two groups, one on each side of the switch shaft, and the test jack and wiper feed connections are mounted beneath the baseplate. The group of sets on the left-hand side of Fig. 2 comprise vertical and rotary off-normal sets 10, 6 respectively, rotary and vertical interrupter springs 17, 14, post springs 20, and spring sets of relays while the right-hand group comprises eleventh step springs 12, sets 35, 36 associated with the rotary and full release magnets respectively, and spring sets of relays such as 52. The rotary off-normal springs 6 are operated by a cam 2 secured to the shaft 1 and having a projection 4 normally engaging an elongated edge of a cranked lever 5 mounted on a virtual vertical axis comprising a pair of set-screws 55 passing through lever 5 with sufficient clearance to permit rocking. Eleventh step springs 12 are similarly operated by cam-projection 3 and lever 11 which is cut away to allow passage for lever 5. The vertical off-normal springs 10 are operated by lever 9 carrying a roller (not shown) engaged by the edge of cam 2. Vertical interrupter springs 14 are operated by a cranked lever 15 pivoted at 18 and having a vertical extension engaging the spring set and a horizontal extension lying in the path of the armature 56 of the vertical magnet. Rotary interrupter springs 17 are operated directly by an extension on the rotary magnet armature, the moving spring of the set being formed with a U-shaped part 19 for engagement by the extension. The post springs 20 comprise two sets 58, 59 either of which is operated by a lever 21 carrying a pair of rollers, only one 23 being shown, adapted to be engaged by projections 24, 25 mounted as desired in one or more of ten holes in a vertical row in a U-shaped member 22 mounted to partake only of the vertical movement of the shaft. The plate 22 also carries a vertical bridging wiper 28 engaging a vertical bank 27 mounted on the switch frame. The double dog is split, both parts 31, 32 being operated by the armature 38 of the normal release magnet while only the part 32 is operated by the armature 33 of the rotary release magnet. The armature 38 operates the spring set 36 by means of a flat spring 37. The spring set 35 is operated by the armature 33 which rocks about a rounded end held against the heelpiece by screws 34, and is held away from the rotary release detent 32 by a flat spring 60 mounted in the set 35. A P.B.X. terminal bank (not shown) mounted in front of the shaft is engaged by bridging wiper 41, and a test jack and wiper feeds are mounted at 42, 43 respectively. A label holder 50 is also provided.